TM 10-6665-297-13&P
2-6
DETECTOR INSTALLATION (continued)
2-6.1
Installing Conduits (continued)
Explosion-proof, weatherproof, diffusion-sampling
Detector #800-086
½ -14 NPT female thread
Explosion-proof, weatherproof, diffusion sampling, corrosion-proof
Detector #0023-7317
½ -14 NPT female thread
The #0023-4014 detector assembly is designed to mount directly in the duct to expose the detector element to
the gases being sampled. Mount #0023-4014 detector in the following manner.
1.
Locate a 1-¼" diameter hole in the duct wall so that detector body can be inserted through the
plate assembly and project into the duct.
2.
Secure the plate assembly to the duct wall using four sheet metal screws through holes provided.
3.
Insert detector body into the plate assembly and secure by tightening the two knurled thumb
screws.
4.
¾ " flexible conduit may be used to allow a convenient means of removing the detector assembly
for servicing.
NOTE: For potentially explosive areas, install wiring in accordance with National Electrical Code
Articles 501-517, which specify explosion-proof fitting, conduit sealing, and special wiring techniques.
2-6.2
INSTALLING DETECTOR WIRING . Use good-quality wire or cable containing three conductors in one
jacket. Install with a minimum number of splices. Cable laid in open trays near AC high-power lines, or
circuits to equipment which may generate radio-frequency (RF) signals, commutation noise, or ignition
noise, should be sheathed or shielded. The outer braid of shielded cable must not contact conduit or
junction boxes, and must be grounded only at the control module end. The cable should contain green,
black, and white wires.
Maximum resistance allowable in black and green (A and R conduit wires is 2.5 ohms per wire (5 ohms
total A and R loop resistance, with A and R wire resistances the same within 0.1 ohm). A 1. 25-ohm
maximum resistance is allowable where two detectors share a common power lead from terminals A
and R to a remote point where power leads split.
Wire gauge may be determined with respect to length of wire run as follows:
23-9617
7/1/76
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